Felix Auger-Aliassime used young, fresh legs to score his first career win over Rafael Nadal as the Canadian stayed alive in Green group round-robin with a  6-3, 6-4 defeat of the veteran.

Nadal is all but eliminated from a semi-final chance after dropping his second of three preliminary matches this week. He has now lost four straight contests, with his last victory coming at the US Open in September.

Defeat also rules Nadal out of the race for year-end No. 1, currently held by his teenaged compatriot Carlos Alcaraz.

FAA, who won three ATP titles on the trot in October, added Nadal to his recent victim’s list which also included a defeat of Novak Djokovic at the Laver Cup two months ago.

“It’s really cool,” the 22-year-old winner who stands 1-1 in the group said. “This is something I could only dream of.. being here one day.

The Canadian added; “The age gap is huge, but Nadal proved what a champion he is.

“He’s playing guys in their young 20s and still moving well and serving well.

“He’s still a very good (player) example.”

FAA dominated with 29 winners while Nadal managed just 12; the Spaniard also failed to convert on all five of his break chances and had 23 unforced errors.

It  took me one match to get used to conditions,” FAA said (he lost to Casper Ruud on Sunday). “But that helped me a lot

“My game was just better today, I was hitting with more consistency, precision and quality

“When I’m playing like this I can beat some of the best in the world. If I can get another win in the group (against Taylor Fritz) hopefully I can get through.”

FAA is part-coached by Nadal’s uncle and own former coach Toni, who also runs his nephew’s tennis camp on the family’s home island of Mallorca.